GM Service Manual Online
For 1990-2009 cars only

The optional engine coolant heater (RPO K05) preheats engine coolant in order to aid cold weather starting. The engine coolant heater operates from a 110 V AC power source through a heating element in the water jacket of the engine block. The heating element warms the coolant as long as the heater cord is plugged into the AC power source.

The unit has a detachable electrical cord. If the heater fails to operate inspect the following components before you replace the heating element:

    • The cord
    • The connections
    • The power supply